What happens if you access a non-existent property...
A). It returns undefined.
B). It throws an error.
C). It returns null.
D). It returns true.
How do you add a new property 'age' with value 25...
A). person.age = 25;
B). person['age'] = 25;
C). person.add('age', 25);
D). person.push('age', 25);
What is the correct way to create an empty object...
A). var obj = {};
B). var obj = ();
C). var obj = [];
D). var obj = <{}>;
How do you add a method to an object created wit...
A). this.methodName = function() {}
B). this.methodName: function() {};
C). this.methodName = () {}
D). this.methodName: () {}
How do you access a property called 'name' from an...
A). person.name
B). person['name']
C). person->name
D). person::name
What is the purpose of the 'this' keyword in a co...
A). It refers to the new object bei...
B). It refers to the global object.
C). It refers to the current object.
D). It refers to the parent object.
What does Object.keys(obj) return?
A). An array of object keys.
B). An array of object values.
C). An array of object properties.
D). An array of object methods.
What is the purpose of the 'super' keyword in a ...
A). It calls methods from the paren...
B). It creates a new instance of the...
C). It refers to the current object.
D). It checks for property existence.
How do you inherit properties and methods from a...
A). class SubClass extends SuperClas...
B). class SubClass inherits SuperCla...
C). class SubClass implements Super...
D). class SubClass derives SuperCla...
What is the output of console.log(obj.prop) if ob...
A). It prints undefined.
B). It throws an error.
C). It prints null.
D). It prints true.